The present invention relates generally sewage flow monitoring and analysis systems. More particularly, the present invention relates to a method and system of analyzing and/or predicting the effect of the inflow and/or infiltration of precipitation on a sewer system.
Tools for the accurate measurement of flow in a sewer network are an important resource for managers, mechanics, engineers, and regulators of municipal and industrial sewer networks. Accurate measurements of flow, and an understanding of what flow is expected to occur during a precipitation event, can help determinexe2x80x94and to predictxe2x80x94when network problems such as overflows, leaks, breaks, clogs, and other blockages and overflows may occur. They can also help system engineers and designers understand when additional capacity must be built into the system, as well as to help them better manage a network with its existing capacity.
Sewer network managers have attempted to analyze and predict what effect a rain event may have on a sewer network, but the prior attempts have been unsatisfactory because they do not provide for reliable, real-time prediction while the rain event occurs, but rather they involve the measurement of a rain event after it is completed and the comparison of the measured event to known data from previous similar events. In addition, the prior attempts to predict rain inflow and infiltration on a sewer network involved significant, detailed modeling efforts, using data relating to the design of the sewer network and/or network discharge sources. Such modeling exercises are time-consuming and costly, and the accuracy of the modeling results depends on how closely modeling conditions to match the conditions under which the modeling was developed.
Accordingly, it is desirable to provide an improved method of, and system for, analyzing and/or predicting the effect of inflow and/or infiltration on a sewer network. The present invention is directed to such a system and method.
It is therefore a feature and advantage of the present invention to provide an improved method of analyzing and/or predicting the effect of inflow and/or infiltration on a sewer network. It is also a feature and advantage of the present invention to provide an improved system for analyzing and/or predicting the effect of inflow and/or infiltration on a sewer network.
In accordance with a preferred embodiment of the present invention, a method of determining the effect of precipitation on flow within a sewer network includes the steps of collecting, at a first location, data representative of a measured rain quantity over a first time interval having a duration that is less than a twenty-four-hour period; maintaining, in a memory, data representative of a modeled rain response at a second location over a second time interval, the second time interval having a duration that is longer than the duration of the first time interval; calculating, in real time, a scaled rain response, the scaled rain response comprising a function of the modeled rain response and the measured rain quantity; and reporting, in real time, the scaled rain response.
Optionally, the second location is a location within a sewer network, and the calculating of the rain response requires no additional data relating to either the sewer network or any substance flowing within the sewer network. Also optionally, each modeled rain response is indicative of an anticipated increase in flow at the second location over the second time interval. The modeled rain response may be capable of graphical representation as a curve on a graph where a y-axis represents at least one of inflow and infiltration and an x-axis represents time. Also, the duration of the first time interval is preferably shorter than a duration of a corresponding precipitation event.
Optionally, the method includes the additional step of identifying a cumulative scaled rain response that corresponds to a sum of a plurality of scaled rain responses over a plurality of time intervals. The method may also include the additional steps of measuring, using a flow meter at the second location, data representative of a measured flow; subtracting a baseline flow from the measured flow to result in an adjusted flow; and comparing, using a processor, the adjusted flow to the scaled rain response to determine whether the adjusted flow substantially corresponds to the scaled rain response. The baseline flow preferably represents expected flow during a non-precipitation event. The comparing is preferably done using a goodness of fit test. If the comparing step determines that the adjusted flow and the scaled rain response do not substantially correspond, an alert may be reported.
In accordance with an alternate embodiment of the present invention, a method of predicting the effect of precipitation on flow within a sewer network includes the steps of collecting data representative of a first measured rain quantity over a first time interval at a first location; creating, using a processor, multiple possible rain responses, wherein each possible rain response represents a possible flow volume distribution at a second location over a second time interval, the second time interval being longer than the first time interval; measuring, using a flow monitor, a measured flow volume distribution at the second location over the second time interval; comparing, using the processor, the possible rain responses to the measured flow volume distribution; selecting, using the processor, a modeled rain response that is the possible rain response that most closely corresponds to the measured flow volume distribution; and storing the modeled rain response, the first measured rain quantity, and the first time interval in a memory.
Optionally, the method also includes the steps of collecting data representative of a second measured rain quantity over a third time interval at the first location; calculating, in real time by a processor, a scaled rain response comprising a function of the modeled rain response and the second measured rain quantity; and reporting, in real time, the scaled rain response.
Also optionally, the second location is a location within a sewer network, and the calculating of the rain response requires no additional data relating to either the sewer network or any substance flowing within the sewer network. Further, the selecting step may include a goodness of fit test on the measured flow volume distribution and the plurality of possible rain responses. Preferably, the modeled rain response is capable of graphical representation as a curve on a graph where a y-axis represents at least one of inflow and infiltration and an x-axis represents time. Also preferably, the first time interval has a duration that is shorter than a duration of a corresponding precipitation event.
As an additional option, the method may include the additional steps of measuring, using a flow meter at the second location, data representative of a measured flow; subtracting a baseline flow from the measured flow to result in an adjusted flow, the baseline flow corresponding to a non-precipitation event; and comparing, using a processor, the adjusted flow to the scaled rain response to determine whether the adjusted flow substantially corresponds to the scaled rain response. With this option, if the comparing step determines that the adjusted flow and the selected rain response do not substantially correspond, an alert may be reported.
In accordance with an additional alternate embodiment, a sewer network flow analysis system includes a processor, a memory in communication with the processor, and a rain gauge in communication with the processor. The processor is programmed to accept, from the rain gauge, data representative of a measured rain quantity over a first time interval that is less than a twenty-four-hour period. The memory maintains data representative of a modeled rain response at a location in a sewer network over a second time interval having a duration that is longer than the duration of the first time interval. The processor is further programmed to calculate, in real time, a scaled rain response comprising a function of the modeled rain response and the measured rain quantity. In addition, the processor is also programmed to report, in real time, the scaled rain response.
There have thus been outlined the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described below and which will form at least part of the subject matter of the claims appended hereto.
In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein, as well as the abstract included below, are for the purpose of description and should not be regarded as limiting in any way.
As such, those skilled in the art will appreciate that the concept and objectives, upon which this disclosure is based, may be readily utilized as a basis for the design of other structures, methods and systems for carrying out the several purposes of the present invention.